This invention relates generally to a fuel system for a tractor, and more particularly concerns a fuel system which incorporates a pair of fuel tanks to store the fuel.
The current trend in the agricultural industry is to increase the size of the unit of land being worked. By increasing the units size, the farmer can increase the efficiency of the time he spends in the fields through utilizing larger tractors to power larger implements.
To further increase his efficiency, the farmer can equip his larger tractor with an auxiliary fuel tank. The additional fuel capacity decreases the number of times the farmer must interrupt his work in the field to refuel his tractor. As a result, he can make better use of the limited time that is available for plowing, planting and harvesting his crop.
The use of these auxiliary tanks, although beneficial to the farmer, does complicate the design of the tractor's fuel system. The complications are produced by the fact that the fuel system must provide the engine with access to fuel from two remotely located storage tanks rather than a single tank.
There are two basic solutions to the problem created by this complication. The first solution involves supplying the fuel individually from each tank to the engine. At a minimum this solution requires a combination of a plurality of sophisticated sensing devices and valving to insure the engine an uninterrupted supply of fuel. It may even include a plurality of sequentially operated pumps to provide the necessary fuel flow.
In light of the extreme complexity of this solution, it carries with it a high cost of designing and manufacturing, as well as a greater susceptibility of the system to the caustic nature of the tractor's environment. The high cost and higher susceptability to failure make this solution the least desirable of the two possible solutions.
The more desirable solution involves interconnecting the tanks. This solution makes it possible to simplify the system by utilizing only one tank as a source of fuel from which the engine's fuel pump draws its fuel supply. Despite the desirability of the second solution, it still complicates the fuel system by requiring a mechanism that will prevent the overflow of one tank caused by the fuel in one tank flowing into the other tank.
A siphon caused overflow can occur in the interconnecting tank solution when one of the tanks is vertically displaced from the other tank by the location of the tanks in the tractor and/or the angle of the tractor on uneven terrain.
In addition, the use of interconnected fuel tanks in the fuel of a diesel engine causes further complications in the system. The additional complication arises from the fact that a diesel fuel system requires a mechanism to recycle the engine's high pressure, unused return fuel into the fuel supply system without disrupting the flow of fuel from the tanks to the engine.
Accordingly, it is an object of the present invention to provide a fuel tank arrangement for a tractor which supplies the tractor's engine with fuel from only one of a pair of interconnected fuel tanks.
More particularly, it is an object of the present invention to provide this type of fuel tank arrangement with a mechanism to eliminate the siphoning of fuel between the tanks.
Finally, it is object of the present invention to provide an interconnected non-siphoning fuel tank arrangement that is compatible with either gasoline or diesel tractor engines.